File Permissions

I changed file permissions on some of the directories in / and now my email does not work. The files are on a remote server running Red Hat Linux ES 3 and I can't login to using Putty either. I can logon using Webmin.

Help! I'm new to linux and was trying to close up permissions for ftp.

Unfortunately, your question is not very good. It is extremely difficult to answer, because it is so vague and very broad with respect to 'everything' not working. Also the amount of information you have provided makes it virtually impossible to offer constructive help. In future try and assign 1 question to 1 problem.

Putty:

1. Can you telnet to port 22:

telnet servername.com 22

If you get something like:

Connected to servername.com (ww.xx.yy.zz).
Escape character is '^]'.
SSH-2.0-OpenSSH_3.6.1p2

then the sshd is working fine. The next bit is the login process. Check /var/log/secure

If the login password is given as correct, then you need to look at the file permissions for the home directory.

Leave the ftp alone, until you've got everything else working (including mail and putty). If you are asking for help on configuration you need to give much more information. e.g:

Problem with email - what MTA are you using (sendmail, xmail, qmail postfix, exim etc) Symptoms, Any specific information from the config file that might be important, log extracts, and any recent events that might have a bearing.

Similarly with ftp. Obviously if you don't know where to find some of the suggested info, at least give the name of teh ftp server software that you are using, so that people can provide you with information as to where to look if necssary.

No need to be sorry - We all have to start somewhere - consider the information as advice. Also try and look at the problem from our perspective. We are all volunteers, and if the question is poor, you can guess what mmost of us will do. Also, the more accurate the question, then the more precise we can be with the answer.

As an aside, I thought I'd add some mail trouble shooting tips.

Not receiving mail?...then try and see if you can connect to the server via the appropriate port (Normally 110 for POP, POP3 or 143 for IMAP)

I pretty sure that it is a permissions issue as that was all that change when things started falling apart. I have not been able to telnet which makes me very handicapped as I am use to Putty and WinSCP to manage files. Both are refused connections. Webmin has a file manament module that is, in my opinion, a real pain to use. When I tried to start the ssh server from Webmin, I received error messages that told me permissions were to open. I closed up permissions per the suggestions until it quit giving errors, but it still does not appear to be starting.

You are telnetting to connect to the port that is used for Putty (ssh) or mail functions (POP and SMTP).

This is used to help you understand how it works, and diagnose what is wrong. The above are 'tests' that will enable you to get putty and mail working again. You should never (from a security perspective) use telnet for remote connections if putty is available and will carry out the same task.

The whole point of the telnet commands is that they tell you how the port is functioning - is it possible to connect to it, is it responding correctly and are there any firewall issues.

Read the links I gave you and you'll start to understand that this is a very useful method of testing.

I am wading through programs checking file and directory permissions. Webmin shows me all the programs and their file status. Quit a few have failed permission checks and then shows what they are to be set as. As I make the changes the status shows OK. It's just taking time.

You need to provide more information with this type of problem. In general , if you get a list of things to try, you should give as much information as possible about the response of the system to that process. In particular, what was the response to:

You guys are right! The ssh problem had nothing to do with permissions. I've never had ssh problems and the server has been running with no issues for over 6 weeks so I was sure that the permissions changes that I made right before the crash was causing all the problems. The problem turned out to be an address that I had left in the config file from some testing a few weeks back. Obviously, I didn't have a need to restart the ssh server or do a reboot until now.

ssh works fine now, and email is working. I still have some permission issues to clean up, but with these two issues resolved, this question has been answered.

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